This book presents the case for the liquid fluoride thorium reactor (LFTR), a unique design whose fissile fuel, uranium-233, would be bred from the abundant fertile nuclide thorium-232 and would undergo fission while dissolved in molten fluorine salts. The book chronicles efforts of the advocates of thorium technology, led by physicist Alvin Weinberg, as they competed in the early years of the nuclear age with the interests of those backing U-235 fueled light-water reactors, headed by Admiral Hyman Rickover. Interviews with Kirk Sorensen, a young engineer who started a company to build LFTRs in 2011, provide insights into both the past and future of thorium technology. The author describes the assets and liabilities of both conventional and thorium reactor technologies in terms understandable to the non-scientist. One chapter focuses on how India and China are pursuing thorium reactor research as they develop their nuclear power industries. The final chapter, "What We Must Do," argues that the time is now for the U.S. to pursue thorium-fueled power. The author is a journalist who has written extensively on issues related to energy.